gaCatalogtree and gaLayers depend on pascalprecht.translate

The catalog tree directive and the layers service just use the `$translate` service, so, really, they don't depend on the ga_translation module but just on the pascalprecht.translate module (recall that the ga_translation pulls the lang selector directive). The importwms and importkml got this [right](https://github.com/geoadmin/mf-geoadmin3/blob/master/src/components/importkml/ImportKmlDirective.js#L10) already, so this PR suggests to do the same for the catalog tree directive and the layers service.

Please review, and merge.